1. Field of Invention
Domestic cats seek perch areas that are highest in order to maintain a sense of security, comfort and stalking advantage. Cats also require surfaces for exercise of their claws and for climbing. Older cats, or those without claws are limited in their climbing ability, but also need an apparatus that provides a challenging climbing experience with stalking advantage. The present invention seeks to address the need for an easily assembled and installed rigid columnar spring tensioned floor to ceiling support structure that can be readily adapted to provide an attractive cat climbing exercise and loft system utilizing a minimum of floor space in the home.
In a preferred embodiment the novel structure of the invention forms a lightweight collapsible segmented rigid center support column incorporating radial stair treads spaced at intervals along the column to form a spiral staircase having a spring assembly at one end for compressive mounting between floor and ceiling. The device is scaleable for varying floor to ceiling heights and location anywhere in a room, providing loft space nearest the ceiling, made in relatively small component parts that can be easily assembled and disassembled and offering compact retail packaging and ease of assembly. These and other objectives of the invention will be more fully understood from the detailed description and drawings.
2. Description of Prior Art
The exercise and perch systems common in the art generally require a large footprint in order to stabilize them and provide safety from falling over. Other prior art structures fail to provide the rigidity and stability for locating the larger functional elements needed to provide perching or resting space near the top with smaller elements near the bottom to minimize floor space.
Among such prior art devices the most basic exercise and scratch device is exemplified by that shown in U.S. Pat. No. 4,253,423 to Kaplan (1981) which consists of a short square post covered by tightly wound rope. This device requires a large base to stabilize a short scratching column in order to balance the weight of the cat and its scratching force and lacks the climbing and elevated perch areas.
U.S. Pat. No. D 355,057 to Northrop (1995) provides a wider base and tapered pole which is also wider at the base to give increased stability during scratching but doesn't provide scalability, climbing or perching and still requires a large floor footprint.
Other designs known in the art take advantage of the spiral staircase concept, but consume inordinate floor space for their height and lack the center core supporting structure giving both vertical and horizontal rigidity and stability needed for high elevation perching. For example, U.S. Pat. No. D 473,020 to DeRaspe-Bolles et al. (2003), and U.S. Pat. No. 6,490,997 to Biermann et al. (2002) use short designs which also narrow as they become taller and provide insufficient resting area at the top. Their limited height fails to satisfy the cat's need for maximum stalking advantage.
Still other known designs provide floor to ceiling climb and perch but suffer significant disadvantages compared to the structure of the present invention. For example;
U.S. Pat. No. D 461,026 to Mason (2002) utilizes a cage-like structure with outer stair tread supports to provide stability requiring a constant diameter the entire length which doesn't allow for minimizing required floor space or ease of assembly and disassembly.
U.S. Pat. No. 3,479,990 to Crow (1969) also shows consistent outside diameter and floor space requirement from floor to ceiling without any of the present invention's means for providing center core vertical and horizontal stability and strength to prevent excessive movement when cats spring from one area to the next. Crow's design takes advantage of being spring biased to the ceiling, but negates the effectiveness of the spring to compensate for fluctuations in floor to ceiling distance owing to changes in materials caused by humidity and the like.
U.S. Pat. No. 3,479,991 to Lichtenberger (1969) like Crow lacks center core stabilizing elements held rigid by compression to minimize movement of the stair treads under loading and unloading. Lichtenberger's device is adjusted in place by the jack screw at the bottom but lacks a spring element to automatically accommodate changes in floor and ceiling distance with changing conditions.
U.S. Pat. No. D 233,844 to Littleton (1974) consumes excessive space by using relatively large rectangular steps at 90° intervals and like the others fails to provide any means for creating center pole stability and rigidity as provided by the central rod of the current device which ties together the multiplicity of column segments (spacers and stair treads) to provide a vertically and horizontally stable rigid structure.
U.S. Pat. No. 3,595,209 to Parker (1971) like Crow, Littleton and Lichtenberger lacks the central compression rod element of the present invention, rather utilizing single round dowels and sockets to join sections failing to stop accidental rotation of steps and lacks a large rest area near the top.
U.S. Pat. No. 3,604,397 to Salerno (1971) provides a floor to ceiling column with just a single shelf midway up the entirely carpeted column. This device seems intended exclusively for cats with claws since it lacks additional steps and forces the cat to jump or claw its way to the perch area. There is no suggestion of a segmented column under compression independent of the tensioning spring holding the column in place between floor and ceiling
U.S. Pat. No. 5,829,390 to Jonilla, et al. (1998) relies on fastening to a wall or doorframe for stability and is therefore not readily relocatable to anywhere in a room
Other structures known in the art such as one sold by Precision Pine Inc. of Knoxville, Tenn. (http://www.catspiral.com) uses vertical spacers but lacks a central compression rod to provide vertical and horizontal stability for the steps and perch. Nor does the Precision Pine structure and similar devices provide the automatic adjustment for temporary changes in floor to ceiling distance. Moreover there is nothing to suggest the rotationally indexed steps forming a spiral staircase of the present invention or the spring biased jack screw assembly for easy insertion of the structure anywhere in the room
As distinguished from the prior art structures the present invention provides a unique versatile climbing, scratching, exercise and resting device for pet cats that is comprised of relatively small component parts that are conveniently packaged in a compact space and readily assembled to form a sturdy, attractive floor to ceiling structure that is alluring to cats encouraging them to exercise by appealing to their instinct to scratch, climb and stalk in a manner that is safe for the cat and the surroundings utilizing minimum floor space with greater utilization of higher spaces.